Endogenous opioid poisoning?
D000368:Aged; D004723:Endorphins / Q000378:metabolism*; D004744:Enkephalin, Methionine; D004745:Enkephalins / Q000378:metabolism*; D005260:Female; D006801:Humans; D009270:Naloxone / Q000627:therapeutic use; D012131:Respiratory Insufficiency / Q000188:drug therapy / Q000209:etiology*
D004723:Endorphins; D004745:Enkephalins; D009270:Naloxone; D004744:Enkephalin, Methionine